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Simple Summary: Bats represent a diverse and ecologically significant mammalian group characterized by different feeding habits. Despite the gut microbiota influence on feeding habits, microbiome studies are scarce in South American bats, in a region considered a hot spot for bat biodiversity. Our study in Southern Brazil compared the gut microbiota of four bat species with different diets: nectarivorous, frugivorous, insectivorous, and hematophagous. We found that each species had unique gut microbiotas linked to their dietary habits, impacting their metabolic potentials. The presence of potentially harmful bacteria varied with feeding habits, suggesting a correlation between diet and microbial pathogens in bats. These insights emphasize the importance of preserving diverse habitats and food sources to support the conservation of bats and their ecosystems. Bats are a diverse and ecologically important group of mammals that exhibit remarkable diversity in their feeding habits. These diverse feeding habits are thought to be reflected in the composition and function of their gut microbiota, which plays important roles in nutrient acquisition, immune function, and overall health. Despite the rich biodiversity of bat species in South America, there is a lack of microbiome studies focusing on bats from this region. Such studies could offer major insights into conservation efforts and the preservation of biodiversity in South America. In this work, we aimed to compare the gut microbiota of four bat species with different feeding habits from Southern Brazil, including nectarivorous, frugivorous, insectivorous, and hematophagous bats. Our findings demonstrate that feeding habits can have a significant impact on the diversity and composition of bat gut microbiotas, with each species exhibiting unique metabolic potentials related to their dietary niches. In addition, the identification of potentially pathogenic bacteria suggests that the carriage of microbial pathogens by bats may vary, depending on feeding habits and host-specific factors. These findings provide novel insights into the relationship between bat feeding habits and gut microbiota composition, highlighting the need to promote diverse habitats and food sources to support these ecologically important species. [ABSTRACT FROM AUTHOR]

Unlike most animals, most bats cannot synthesize vitamin C endogenously. Consequently, this vitamin must be obtained from the diet. Among the bat species, there are several food groups, such as frugivorous, nectarivorous, insectivorous, and hematophagous. In this work, we measured and compared vitamin C levels in different organs of four species of bats, all collected in southern Brazil. When analyzing and comparing the levels of vitamin C in the four bat species, (regardless of the organ), no significant differences were observed. However, when analyzing and comparing the levels of vitamin C in the four organs (regardless of the species), significant differences were observed, with the highest concentrations in the heart, followed by the liver and brain, while the lowest concentration was measured in the kidneys. Additional differences in the levels of Vitamin C were only observed when each organ was analyzed according to the species/diet. These results indicate a high degree of metabolic homeostasis in bats despite the marked difference in the type of diet. [ABSTRACT FROM AUTHOR]

How species persist in fragmented habitats is essential to understanding species resilience in response to increasing anthropogenic pressures. It has been suggested that expansion in dietary niche allows populations to persist in human‐modified landscapes, yet this hypothesis has been poorly tested in highly diverse ecosystems such as tropical forests where frugivory is ubiquitous. Here, we measured dietary niche expansion of a large forest‐dwelling mammal, the white‐lipped peccary (Tayassu pecari), in the Atlantic Forest, Brazil, by comparing its diet using stable carbon (δ13C) and nitrogen (δ15N) isotopes. We collected hair of white‐lipped peccaries in three continuous and three fragmented forests and compared δ13C and δ15N values, resource use and isotopic niches among populations and between forest types. We also tested the relationship between isotopic values of the populations and the forest cover percentage. White‐lipped peccaries fed mainly on forest sources (C3 resources), especially in continuous forests, but 28% of the individuals in fragmented sites also incorporated C4 resources to some extent. In fragmented forests, the populations had isotopic niches from 3‐ to 3.6‐fold the size of those in continuous forests. This niche expansion was due to the consumption of food items with higher δ15N values and C4 crops. Differences among populations were larger among fragmented forests, suggesting variable site‐specific strategies to cope with habitat loss. The mean isotopic values of white‐lipped peccary populations were negatively correlated with the loss of forest cover. Some small forest fragments might still retain relatively high habitat quality, and white‐lipped peccaries might be able to capitalize on such variety of resources, shifting their diets from those observed in continuous forests. We suggest that high dietary flexibility and dietary expansion toward consumption of non‐forest resources might facilitate the persistence of large frugivores in fragmented habitats. [ABSTRACT FROM AUTHOR]

Large ground-dwelling Neotropical gamebirds are highly threatened by habitat loss and hunting, but conservationists rarely attempt to distinguish between these two threats in the management of populations. We used three different types of species records to determine the status (i.e. persistence level) of the Endangered red-billed curassow Crax blumenbachii in 14 forest remnants in north-east Brazil, as either persistent, precarious or extirpated. We related these persistence levels to variables measured in a 2-km buffer radius, including variables associated with habitat quality (proportion of forest cover, length of rivers, patch density, distance from rivers) and hunting pressure (proportion of cacao agroforests and farmlands, length of roads, total area occupied by settlements, distance from roads and from settlements). Curassows were more persistent in forest patches located (1) more distant from settlements, (2) in landscapes with few settlements, (3) in landscapes with a high incidence of roads, (4) in a mosaic with a high proportion of forest, shaded cacao agroforest and farmland, and (5) more distant from other forest patches. Hunting pressure potentially exerts more influence on persistence than habitat quality: (1) hunting pressure submodels had a higher explanatory power than habitat quality submodels, (2) final models comprised four hunting pressure variables but only two habitat quality variables, and (3) hunting pressure variables appeared in all models whereas habitat quality variables appeared in only one final model. If hunting pressure is driving declines in curassows, regions with low human presence and a high proportion of forest cover are recommended for establishing new reserves. [ABSTRACT FROM AUTHOR]

Mutualistic interactions between animals and plants are essential for ecosystem functioning, providing ecosystem services such as pollination and seed dispersal. The temporal dynamics of plant phenology and animal abundance, induced by seasonal variation in precipitation and resource availability, may influence the structure of animal-plant interaction network. In this paper, we analyzed the mutualistic network structure between birds and plants in a seasonally tropical dry forest in Brazil during the dry and rainy seasons. We recorded 160 interactions between 21 bird species and 11 plant species. In general, networks had low connectance (C = 26%), nestedness (wNODF = 27.54), and modular pattern (Qw = 0.33). Despite the number of interactions being higher in the rainy season, network parameters were consistent across the seasons and presented no explicit differences. However, the network connectance was slightly higher in the rainy season than in the dry season, while the specialization index was higher in the dry season than in the rainy season. Elaenia sp., Mimus saturninus , and Cyanocorax cyanopogon were the bird species that presented the highest number of links. On the other hand, Xiquexique gounellei, Cereus jamacaru , and Pilosocereus pachycladus were the most consumed plant species. The generalized pattern observed suggests that bird-plant interaction in Caatinga may be appropriate to the variable and irregular patterns found in dry forests. Our data reinforce the role of species of the Cactaceae family in maintaining bird communities in semiarid environments. Therefore, due to the high functional importance of those cacti species in influencing both the network stability and the species maintenance in the community, priority attention should be given to them in conservation programs. • Plant-frugivore mutualistic network in a dry forest fragment shows a generalized pattern of interactions. • Interaction network parameters are consistent across the dry and rainy seasons and had no explicit differences. • Our data reinforce the role of the Cactaceae in maintaining bird communities, especially in periods of resource scarcity. [ABSTRACT FROM AUTHOR]

Forest fragmentation demonstrably alters plant species composition, distribution, and diversity, and, in turn, may affect the availability of food resources for primary consumers. We investigated to what extent fragmentation affected the diets of 6 groups of bearded saki monkeys (Chiropotes chiropotes) living in two 10-ha fragments, two 100-ha "fragments" that were no longer fully isolated, and 2 areas of continuous forest in central Amazonia. When changes occurred we tested whether differences in diet were due to plant species availability by comparing the prevalence of consumed items against their relative abundance at the 6 sites. In total, the monkeys consumed fruits, seeds, flowers, and leaves of 244 plant species, of which less than 2% were shared among all 6 groups. Although there was a positive correlation between relative abundance of diet species and consumption frequency, monkeys did not eat all available potential resources, and groups inhabiting the 10-ha fragments consumed items that were ignored in larger forested areas. Our findings suggest that bearded sakis living in small forest fragments are limited in their dietary choices as a consequence of the reduced number of plant species present, and therefore consume species that monkeys inhabiting continuous forests typically can ignore. We conclude that the ability to consume a diverse diet that includes seeds and unripe fruit helps this species survive in forest fragments, but it appears that these conditions are unviable unless connectivity increases among the forest fragments and continuous forest in the landscape. [ABSTRACT FROM AUTHOR]

We tested for geographic patterns in fruit colour diversity. Fruit colours are thought to promote detection by seed dispersers. Because seed dispersers differ in their spectral sensitivities, we predicted that fruit colour diversity would be higher in regions with higher seed disperser diversity (i.e. the tropics). We collected reflectance data on 232 fruiting plant species and their natural backgrounds in seven localities in Europe, North and South America, and analysed fruit colour diversity according to the visual system of birds—the primary consumer types of these fruits. We found no evidence that fruit colours are either more conspicuous or more diverse in tropical areas characterised by higher seed disperser diversity. Instead, fruit colour diversity was lowest in central Brazil, suggesting that fruit colours may be more diverse in temperate regions. Although we found little evidence for geographic variation in fruit hues, the spectral properties of fruits were positively associated with the spectral properties of backgrounds. This result implies that fruit colours may be influenced by selection on the reflectance properties of leaves, thus constraining the evolution of fruit colour. Overall, the results suggest that fruit colours in the tropics are neither more diverse nor more conspicuous than temperate fruits, and that fruit colours may be influenced by correlated selection on leaf reflectance properties. [ABSTRACT FROM AUTHOR]